Let ignorance pretend to admire these striking results, and laugh at him who is anxious to discover the cause which produces them; he has incomparably more interest and pleasure, his eyes more open, and his understanding more exercised in these common facts, than other men, while yet he deems them as nothing compared to the end they serve; they are indeed interesting in themselves, but to him they are most interesting, because he considers them the means, but still only as the means, by which he obtains the noblest object which the light of his reason can discover—the discovery of those principles, or of that order of operation of the cause which produces them. Medical libraries are full of books on the influence of seasons and climate, miasmata, malaria, and other local causes of disease: and they admit also that the influences of all these are such, that almost all diseases common to man will exhibit altered and corresponding symptoms under these varying circumstances, proving they participate in, and are conjoined (or “tinged as it were,” as it is said by some,) with them. All this, however, I leave for the Essay on the Atmosphere, but I mention these facts and observations in the mean time for the sake of this argument, that if all these modifications are admitted to exist among the sane, how much more strikingly must the peculiar circumstances, the singular habits, and the altered state of mind of the insane, modify the effects of this influence:—so strikingly, that I have no doubt, from these causes, may be explained the very singular exhibitions in this last-mentioned case. Where the particular state of mind, and the peculiar circumstances connected with his confinement, have superinduced in the system the irregular accumulation and expenditure of the nervous energy, so that, though the increase of the animal spirits was, in the first instance, the common effect of a cause operating in and through all, every where,—yet, operating through, and modified by, the peculiarities connected with his case, has in time produced in him, as well as in a less striking degree in others, and in fact, in many, though certainly not in all cases of insanity, effects so very singular and striking.